You control the execution mode by using environment variables or by specifying options in the PERFORMANCE statement. The important environment variables follow:
grid host identifies the domain name system (DNS) or IP address of the appliance node to which the OPTGRAPH procedure connects to run in distributed mode.
installation location identifies the directory where the SAS high-performance software is installed on the appliance.
data server identifies the database server on a Teradata appliance as defined in the hosts file on the client. This data server is the same entry that you usually specify in the SERVER= entry of a LIBNAME statement
for Teradata. For more information about specifying the LIBNAME statements for Teradata and other relational databases, see
the SAS/ACCESS Interface documentation for the specific database.
The key variable that determines whether the OPTGRAPH procedure executes in distributed mode is the grid host. If no grid
host is specified, PROC OPTGRAPH runs in single-machine mode on the client. The installation location and data server are
needed to ensure that a connection to the grid host can be made. Specifying a data server is necessary only on a Teradata
appliance and depends on the entries in the client hosts file. The hosts file specifies the server (with a suffix that consists of "cop" and a number) and an IP address. For example:
myservercop1 33.44.55.66
You can set an environment variable directly from the SAS program by using the OPTION SET= command. The following example shows the grid host and installation location options as they might be specified for a Greenplum appliance (no data server option is needed):
option set=GRIDHOST ="grid001.example.com"; option set=GRIDINSTALLLOC="/opt/TKGrid";
Similarly, the following example shows the grid host and installation location options as they might be specified for a Teradata appliance:
option set=GRIDHOST ="grid001.example.com"; option set=GRIDINSTALLLOC="/opt/TKGrid";
Alternatively, you can set the parameters in the PERFORMANCE statement in the high-performance procedure. For example:
performance host ="grid001.example.com"
install ="/opt/TKGrid";
A specification in the PERFORMANCE statement overrides a specification of an environment variable without resetting its value. An environment variable that you set in the SAS session with an OPTION SET= command remains in effect until it is modified or until the SAS session terminates.